#!/usr/bin/python3

# project euler. problem 1

# if we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3,5,6,9. the sum of these multiples is 23. Find the sum of all the multiples of 3 or 5 below 1000.


if __name__=="__main__":
    sum = 0;
    for i in range(1000):
        if i%3==0 or i%5==0:
            sum +=i;

    print(sum);
        
    
